Two grisly deaths in four days have residents and business owners in San Francisco's Lower Haight fearful their neighborhood could be slipping back into its more violent past.

On Friday, 53-year-old neighborhood resident Anthony Jones was stabbed to death on the 500 block of Page Street by a man he had bludgeoned in the head with a shovel in a fight, police said. Just around the corner, at Rose and Webster streets, an unidentified woman's body was found early Monday inside a burning car.

Authorities are considering whether to file charges against the surviving combatant from Friday's fight, whose name has not been released, and they're looking into the circumstances of the unidentified woman's death. Residents are anxiously awaiting word.

Dick Vivian, owner of Rooky Ricardo's Records for 24 years, said the Lower Haight has been on the way up but that recently, "there's an energy on the streets that feels very five years ago."

"We're falling back into the ways we've been trying to fix," said Vivian, who met with police and other business owners Monday to discuss neighborhood safety. "We can't let that happen."

Vivian said new restaurants and clothing stores have attracted foot traffic to his stretch of the Lower Haight east of Fillmore Street. The bustling atmosphere has kept a decades-old drug trade - and the violence that came with it - at bay, he said.

Quentin Manchester, 39, a Rose Street resident for five years, said he knew Jones from around the neighborhood. Manchester said Jones had been complaining about a long-standing conflict with the man he eventually hit with a shovel.

On Monday, Manchester said, he was awakened by an explosion on his street about 3:15 a.m. and saw a car engulfed in flames. Firefighters found the woman's body in the car after putting out the blaze.

"It's sad and scary that someone could get killed right here - again," Manchester said.

An elderly Rose Street resident said he had seen a man wearing gray pants light a rag on fire and toss it into the driver's side of the car before running north on Webster Street.

The resident, who declined to give his name because he feared retribution, said he had told police he was looking out his second-story window because he liked to keep an eye on the alley, which was once known for drugs and prostitution.

"They cleaned up most of the drug dealers from this area," the man said, "but they can't keep all the bad men away."